Friday, November 27, 2015

Today is the 25th anniversary of ARM Ltd., UK. To celebrate and honor their amazing work, we present the Visual ARM1, created in collaboration with some of ARM's founding engineers.

Designed by Sophie Wilson and Steve Furber before there was an ARM Ltd., the Acorn RISC Machine was the first of a line of processors that power our cell phones and tablets today. Unlike our projects based on microscope images, the Visual ARM was created from a resurrected .cif chip layout file, used under our license agreement with ARM. We also photographed one of the few ARM1 chips at very high resolution, and our photograph is featured at the Centre for Computing History in Cambridge.

Credit goes to ARM founding engineers John Biggs for inspiring the project, discovering the tape, and recovering a usable .cif file, Lee Smith for spotting the variable record format used to encode the file (an artifact of the VMS on Acorn's VAX that at first appeared to be widespread corruption of the file), to Cambridge University Computing Services for reading the Exabyte tape, and to ARM founder Dave Howard for help unraveling the VLSI CIF dialect. Our chip simulation and visualization was developed by Barry Silverman, Brian Silverman, Ed Spittles, and Greg James.

Saturday, October 11, 2014

This Python version uses the same 6502 circuit node names and ids as our web-based javascript version but has no polygon geometry. It includes our full netlist model of the Atari TIA and a simple emulation of the PIA, aka RIOT, and program ROM. Leave it running long enough, and it'll render frames from classic games.

The simulation provides a cycle-accurate picture of what the console is doing based on the physical parts of its microchips.

While our decapping and delayering here on the west coast have taken a short break, Christian Sattler in the UK has stepped up and run several chips through the chemistry. Among them is our Atari POKEY. Christian also has an interactive browser to view the aligned layers. Enjoy!